Bubble machine



FIG. 1 is a perspective view of the bubble machine;

FIG. 2 is a front elevational view of the bubble machine;

FIG. 3 is a back elevational view of the bubble machine;

FIG. 4 is a left side elevational view of the bubble machine;

FIG. 5 is a right side elevational view of the bubble machine;

FIG. 6 is a top plan view of the bubble machine; and,

FIG. 7 is a bottom plan view of the bubble machine. 

The ornamental design for a bubble machine, as shown. 